Evaluation of debris remnants and different calcium silicate-based sealers in isthmuses of mesial roots of mandibular molars

Author(s)

David Saldanha de Brito Alencar

• Document type: Master's Dissertation
• Press: Piracicaba, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Odontologia de Piracicaba
• Defense date: 2023-03-30

Examining board members

Marina Angélica Marciano; Maraisa Greggio Delboni; Carlos Augusto de Morais Souto Pantoja

• Advisor: Marina Angélica Marciano

Abstract

This work was divided into two independent studies, but with shared samples, first, the aim of study 01 was to evaluate the removal of debris in regions of canals and isthmuses after the use of auxiliary irrigation systems, and the aim of study 02 was to evaluate the remaining of filling material in canals with isthmuses of mesial roots of mandibular molars. 100 mesial roots of lower molars were sectioned at 6, 4 and 2 mm from the root apex and then irrigated with 2.5% sodium hypochlorite (n=50) or 2% chlorhexidine gel with saline solution (n=50), the irrigants were agitated (n=10) using passive ultrasonic irrigation (PUI), XP-endo Finisher, EQ-S, Easy Clean or manual irrigation with syringe/needle (without agitation). All root canals were instrumented with R25. The sections were evaluated considering the occupied area (in percentage) of debris (in canals and isthmuses) in scanning electronic microscopy (SEM) in a non-destructive way. In sequence, the teeth were filled (n=20) using rhodamine B 0.1% associated with powder/liquid BioRoot RCS or MTApex cements, ready to use EndoSequence BC Sealer HiFlow or Bio-C Sealer, or epoxy resin-based sealer AH Plus Jet. After 30 days, retreatment was performed using R40 and XP-endo Finisher R under irrigation with 2.5% sodium hypochlorite, then the remaining area of filling material was analyzed through confocal microscopy. The retreatment time was recorded, as well as the setting time, using both methods (moist and dry) according to the ISO-6876:2012 standards. Statistical analyzes and multiple comparisons used a significance level of 5% (p < 0.05). In the root canal region, 2% chlorhexidine gel was more efficient in removing debris using PUI at 6 mm, and PUI or Easy Clean at 4 mm. However, in the isthmus region, no statistical difference was found. Regardless of the agitation method, the protocol of 3 activations, lasting 20 seconds each, significantly reduced the remaining of debris. The AH Plus Jet exhibited a greater amount of remaining filling material in 2 mm in the canal and isthmus region, as well as having a longer retreatment time. Setting time, in both moist and dry methods, was affected considerably for EndoSequence BC Sealer HiFlow. In conclusion, the use of supplementary forms of cleaning and the agitation of the irrigants solutions improved the removal of debris. Remnants of filling material remained in the canals and are irrespective of the endodontic sealer (AU)

• FAPESP's process: 21/03171-7 - Evaluation of the remnant of different calcium silicate-based cements in mesial root isthmus of mandibular molars
• Grantee: David Saldanha de Brito Alencar
• Support Opportunities: Scholarships in Brazil - Master